I get up too fast. There is a great rushing of blood; my vision darkens. In my ears is the rhythm of my own heart's beat, only different. Swift and stacatto, distant and echoing... Can you hear it? Have you heard it before?
It sounds exactly like a fetal doppler: wop-wop-wop-wop-wop-wop-wop-wop-wop.
Gradually my sight clears. The eerie sound stops as suddenly as it started, which is somehow worse than the jarring onset of the sound itself. I discover, then, that I am cold, and I cannot remember how to breathe.